Once-monthly paliperidone palmitate compared with conventional and atypical daily oral antipsychotic treatment in patients with schizophrenia

Abstract

Objective This analysis of the Paliperidone Palmitate Research in Demonstrating Effectiveness (PRIDE) study (NCT01157351) compared outcomes after administration of once-monthly paliperidone palmitate (PP) vs conventional oral antipsychotics (COAs) or atypical oral antipsychotics (AOAs). Methods PRIDE was a 15-month study of 444 individuals with schizophrenia and a history of incarceration. They were randomly assigned to PP or to 1 of 7 commonly prescribed OAs. Primary endpoint was time to first treatment failure (TF). Event-free probabilities were estimated using the Kaplan-Meier method; treatment group differences (PP vs COAs, PP vs AOAs, and PP vs oral paliperidone/risperidone) were assessed using a log-rank test. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression models. No adjustment was made for multiplicity. Results Compared with PP, risk for first TF was 34% higher with COAs (HR: 1.34; 95% CI: 0.80-2.25), 41% higher with AOAs (HR: 1.41; 95% CI: 1.06-1.88), and 39% higher with paliperidone/risperidone (HR: 1.39; 95% CI: 0.97-1.99). Incidences of extrapyramidal symptom-related adverse events (AEs) were 45.7%, 13.7%, and 10.6% in the COA, AOA, and oral paliperidone/risperidone groups vs 23.9% in the PP group. Incidences of prolactin-related AEs were 5.7%, 3.8%, and 3.5% vs 23.5%, and incidences of ≥7% weight increase were 11.4%, 14.9%, and 16.0% vs 32.4%. Conclusions Results suggest a lower risk of TF but a higher rate of some AEs after treatment with PP vs COAs, AOAs, and paliperidone/risperidone. Deselection of specific OAs and low patient-compliance rates with OAs likely biased the safety results.